Canister tapping device

ABSTRACT

A canister tapping device is comprised of a support frame adapted to support a canister containing a fluid and having opposite walls, first and second piercing tubes movably mounted to the frame and facing the opposite walls of the canister, and a movable mechanism interconnecting first and second piercing tubes, the piercing tubes being movable from first positions wherein they are spaced from the opposite walls of the canister to second positions wherein they puncture the walls. The mechanism is adapted to be moved by means of a handle to cause the piercing tubes to be moved between their first and second positions.

United States Patent Joseph Carl Dawson;

Jay B. Brown; Euel C. Pryor, all of 93 Ford Lane, St. Louis, Mo. 63042 Appl. No. 823,673

Filed May 12, 1969 Patented June 15, 1971 lnventors [56] References Cited UNITED STATES PATENTS 3,385,475 5/1968 Loe 222/835 Primary Examiner David M. Bocltenek Attorneys-John D Pope lIl ABSTRACT: A canister tapping device is comprised of a support frame adapted to support a canister containing a fluid and having opposite walls, first and second piercing tubes movably mounted to the frame and facing the opposite walls of the canister, and a movable mechanism interconnecting first and second piercing tubes, the piercing tubes being movable from first positions wherein they are spaced from the opposite walls of the canister to second positions wherein they puncture the walls. The mechanism is adapted to be moved by means of a handle to cause the piercing tubes to be moved between their first and second positions.

PATENTED JUN] 5 I9?! SHEET 1 UF 4 FIG.

7 INVENTORS JOSEPH CARL DAWSON EUEL BY PATENTEU JUN 1 5 I971 SHEET 2 BF 4 FlG.3

FIG.4

INVENTORS JOSEPH CARL DAWSON JAY B. BROWN EUEL .PRYOR w ATTOR EY FIG.5

PATENTED JUN] 5mm 3584.767

SHEET 3 OF 4 FIGS INVENTORS JO5EPH CARL DAWSON JAY B. BROWN EUEL C. PRYO BY W M ATTORNEY PATENTEU JUN 1 5x971 SREU l [1F 4 Free INVENTORS JOSEPH CARL DAWSON JAY B. EUEL BY BROWN C. FRY? M b. w ATTORN EY CANISTER TAPPING DEVICE This invention relates to devices for tapping canisters and more particularly to a canister tapping device which punctures the walls at opposite ends of the canister.

Canisters for fumigants and other materials are customarily tapped through bungholes located at the center of the top wall of the canister. Opening of the bungholes for removal of the contents can be a hazardous practice when the contents of the canister are poisonous or toxic. The primary hazard arises from the danger that some of the contents may escape and strike someone in the face or that someone will inhale poisonous fumes emitted from the bunghole.

Canister tapping devices have been provided which puncture the side walls of cylindrical canisters by tightly embracing the canister and driving a beveled piercing tube through the canister sidewall adjacent its bottom margin. Usually an elastomeric seal is disposed immediately to the rear of the piercing tubes cutting edge and this seal is compressed against the outwardly presented surface of the canister so as to seal the margins of the puncture.

Sometimes two taps are provided in the canister, one for introducing air pressure and the other for removing the material from the canister. The pressure aids in removing the contents. For the most effective operation of these two taps, the air pressure inlet tap should be disposed at the top of the canister so that the air will be introduced where it will not bubble through the contents of the canister. The exit tap should be provided at the bottom of the canister so that substantially the entire contents of the canister may be removed. However, most canister tapping devices are incapable of tapping both ends of the canister at once.

Among the several objects of the present invention may be noted the provision of a canister tapping device which taps both ends of the canister at once; the provision of a canister tapping device which permits removal of the contents from the canister without the necessity of inverting the canister; the provision of a canister tapping device which maintains an airtight seal around piercing tubes after they have punctured the canister; the provision of a canister tapping device which includes means for holding the piercing tubes in sealed engagement with the canister; the provision of a canister tapping device which permits introduction of air pressure through the top of the canister so that the contents maybe forced out ofa bottom tap hole; the provision of a canister tapping device which permits the operator to tap the canister from a position spaced from the canister so as to avoid being struck by any of the contents during the puncturing operation; the provision of a canister tapping device which utilizes leverage to permit the manual application of force to the piercing tubes sufficient to cause them to puncture the canister; the provision of a canister tapping device which provides a positive grip of the canister after it has been tapped; and the provision of a canister tapping device which is economical to manufacture and durable in use. Other objects and features will be in part apparent and in part pointed out hereinafter.

The invention accordingly comprises the constructions hereinafter described, the scope of the invention being indicated in the following claims.

In the accompanying drawings, in which one of various possible embodiments of the invention is illustrated,

FIG. 1 is a side 'elevational view disclosing the canister tapping device; a

FIG. 2 is a perspective view of the canister tapping device;

FIG. 3 is a sectional view taken along line 3-3 of FIG. 1;

FIG. 4 is an enlarged fragmentary view of the base of the canister tapping device showing the piercing mechanism, the operating mechanism, and the canister;

FIG. 5 is a bottom view of the canister tapping device;

FIG. 6 is a top view of the canister tapping device with the cover broken away;

FIG. 7 is a sectional view of one of the'piercing tips of the canister tapping device;

FIG. 8 is a partial sectional view through the upper portion of the canister tapping device;

FIGS. 9 and 10 are perspective views showing the detail the bottom bracket, and the block which is associated with the bottom bracket;

. FIGS. 11 and 12 are sectional views taken along lines 11-11 and 12-12, respectively, of FIG. 1; and

FIG. 13 is a perspective view of the lever of the canister tapping device.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Numeral 8 designates a'canister tapping device. A vertical framework 10 includes a single base of heavy sheet metal having two parallel side members 12, 14, each of which has outwardly angled flanges 16, 18 (FIG. 11). Side members 12, 14, are joined by a back member 20, and togetherthey form a means for receiving and embracing the cylindrical walls of a canister 22. At the upper end of framework 10 (FIG. 12), side members 12, 14, and flanges 16, 18, are the same as at the lower end (FIG. 11), but back member 20 has been cut in the middle and bent outwardly to form extensions 24, 26, of side members 12, 14.

Welded to the bottom of framework 10 is a base 28 having the shape of a rectangular box. At the lower edge of base 28 are flanges 30 having holes 32 for mounting the canister tapping device on a floor or another piece of equipment. There is a rectangular hole 34 in the top of base 28 (FIG. 2). At the upper end of framework 10 is a top 40. All the details of construction of top 40 are identical to base 28 with the exception that there are no flanges extending outward from top 40 and top 40 has, in addition, a metal cover 42 secured thereover to protect the working mechanism therein.

A lever 44 has a pair of parallel arms 45 joined at one of their ends by a handle 46 and at the other by a shaft 48. Shaft 48. is pivotally mounted on framework 10 to provide a fulcrum for lever 44. A pair of pins 50 are welded to lever 44 adjacent the opposite ends of shaft 48. Pins 50 are positioned so that they move in an arcuate path about shaft 48 during pivoting of lever 44. A stop 51 (FIG. 13) is also provided on lever 44 for limiting its downward pivotal movement by engaging framework 10.

A pair of handle links 52 each has one of their ends pivoted on pins 50 and the other pivoted to a rocker arm 54. Rocker arm 54 has a pair of parallel rocker members 56 which are joined at their opposite ends by shafts 58, 60. A pivot shaft 62 extends between rocker members 56 midway along their lengths and is journaled in side members 12, 14, of framework 10. Pivotally secured to shafts 58, 60, are an upper tensioning rod 64 and a lower tensioning rod 66, respectively. When handle 46 is moved downwardly lever 44 rotates in a counterclockwise direction about shaft 48 as do pins 50. This causes handle links 52 to move downward and because of their pivotal attachment to rocker arm 54 they rotate rocker arm 54 in a counterclockwise direction. The counterclockwise rotation of rocker arm 54 causes upper rod 64 to be pulled downwardly and lower rod 66 to be pulled upwardly.

Referring to FIGS. 4 and 5, lower rod 66 terminates at its lower end in a fitting 68. A punch lever 70 provides a tube mounting means and has two parallel members 72 which are joined at one of their ends by a pivot shaft 74 and at the other by a welded bracket 76. Pivot shaft 74 is mounted between a pair of brackets 75 and provides pivotal connection of punch lever 70 to base 28. Bracket 76 supports a fitting 78, a nut 80, and a piercing tube 82 having a beveled cutting edge 83. An elastomeric O-ring 84 surrounds piercing tube 82, and is mounted in a beveled recess provided by nut (FIG. 7). Tube 82 is retained in welded bracket 76 by an'ell 88. When piercing tube 82 punctures canister 22, it provides communication from the interior of canister 22 to ell 88. Fitting 68 of lower rod 66 is pivotally connected to punch lever 70 intermediate its ends by means-of a shaft 89-50 that when lower rod through rectangular hole 34 in base 28.

A flexible hose 94 interconnects ell 88 of tube 82 with an outlet fitting 100 which is mounted in one of the walls of base 28. This provides an outlet conduit which permits withdrawal of the contents of canister 22.

A pressure inlet fitting 102 is also mounted in the wall of base 28. A pressure inlet tube 108 has one of its ends operatively connected to pressure inlet fitting 102, and extends upwardly through base 28 along the inside of framework 10. Tube 108 terminates at its upper end inside top 40 where it is connected to a hose 114 which is in turn connected to an ell 120 (FIG. 6).

Referring to FIGS. 6 and 8, ell 120 retains a fitting 122 in a welded bracket 124. A nut 126 connects an upper piercing tube 130 to fitting 122. Around upper piercing tube 130 is an elastomeric O-ring 132. Bracket 124 is weldably secured to an upper punch lever 134 which is identical in construction to lower punch lever 70 and is pivotally secured at one ofits ends to top 40 by means of a shaft journaled within a bracket 135. The extreme upper end of upper rod 64 is pivotally secured intermediate the opposite ends of punch lever 134.

When handle 46 is depressed it causes handle links 52 to rotate rocker arm 54 in a counterclockwise direction. This causes upper tensioning rod 64 and lower tensioning rod 66 to be pulled downwardly and upwardly, respectively, which in turn causes lower punch lever 70 to pivot upwardly and upper punch lever 134 to pivot downwardly so that lower piercing tube 82 and upper piercing tube 130 are moved towards one another. Thus rocker arm 54, upper tensioning rod 64, andlower tensioning rod 66 provides a movable mechanism which interconnects punch levers 70, 134, and causes piercing tubes 82, 130, to move from their spread position to their closed position.

When canister 22 is positioned between upper piercing tube 130 and lower piercing tube 82 depression of handle 46 causes the piercing tubes to puncture the opposite ends of the canister. Both the bottom and the top of canister 22 are spherically concave. Tubes 82, 130, are positioned on punch levers 70, 134, so that they strike squarely against the concave ends of canister 22. At the point of contact, the longitudinal axes of piercing tubes 82, 130, are normal to lines which are tangent to the curved ends of canister 22. Because tubes 82, 130, strike squarely against the ends of canister 22, O-rings 84, 132, will make complete contact with the canister around the piercing tubes and provide a seal as the tubes puncture the opposite ends of canister 22. The ends of canister 22 are dented slightly by the piercing action and O-rings 84, 132, are therefore retained in a triangular annular recess between nuts 80, 126, and the ends of canister 22 (FIG. 7), so that internal pressure from the canister cannot cause the O-ring to blow-out." When handle 46 is fully depressed, nut 80 of lower tube 82 makes complete metal-to-metal contact with the canister bottom and nut 126 of upper tube 130 makes metal-to-metal contact with the canister top.

Beneath top 40 is an angle iron 136 which provides additional strength and support. Angle iron 136 distributes the downward force from bracket 135 to framework 10.

Pivotal connection of lever 44 to framework is provided by a floating mount 137 assembled on framework 10. Floating mount 137 includes a bolt 138 which is retained within a bracket 140 by nuts 142. Bolt 138 terminates in a flange 144 which is rigidly secured to the lower end of bolt 138. A coil spring 146 has its upper end bearing against the lower surface of flange 144 and its lower end bearing against a block 148 so that it urges block 148 downwardly. Block 148 has a downwardly presented arcuate indentation 150 (FIGS. 8 and 10) which is adapted to receive shaft 48 of lever 44. A bottom bracket 152 is rigidly secured to framework 10 (FIGS. 8 and 9) and has two arms with a pair of upwardly presented arcuate indentations 154 which embrace the bottom of shaft 48. Shaft 48 is held in position between downwardly presented arcuate indentation 150 of block 148 and upwardly presented arcuate indentation 154 of bottom bracket 152. Because bottom bracket 152 is rigidly secured to framework 10, it prevents any downward movement of shaft 48 of lever 44. However, shaft 48 is movable upwardly'against the bias of spring 146. Spring 146 holds shaft 48 against bottom bracket 152 when there are no upward forces acting on shaft 48.

During the operation of the canister tapping device, canister 22 is placed against vertical framework 10 between the projections of base 28 and top 40 on the side of framework 10 opposite lever 44 (FIG. 1). To insert canister 22 into the canister tapping device lever 44 must be in the extreme upward position so that piercing tubes 82, 130, are in their spaced position and are spaced from the opposite ends of canister 22. After the canister is inserted into the canister tapping device lever 44 is moved downward by means of handle 46 until it is in a horizontal position. At this point tubes 82, 130, engage the bottom and top of the canister'respectively. Further depression of handle 46 moves pins 50 counterclockwise about shaft 48, but because of the resistance of the top and bottom of canister 22 to puncture, shaft 48 is pried upwardly in a direction perpendicular to its rotational axis against bearing block 148, thereby compressing spring 146. Pressure on handle 46 is increased until spring 146 resists compression to such an extent that piercing tubes 82, 130, puncture the canister walls. As soon as the initial puncture is made, resistance of the canister walls to tubes 82, 130, is suddenly reduced and much less pressure is required to move tubes 82, 130, on into the canister. This sudden reduction in resistance causes coil spring 146 to plunge tubes 82, 130, into the canister walls so that 0- rings 84, 132, are firmly seated quickly after the initial puncture. The piercing interval is so brief that a minimum of fluid escapes even when the contents of canister 22 are under pressure before opening. During the puncturing operation, handle 46 is depressed until stop 51 (FIG. 13) contacts the back of framework 10. At this point pins 50 have rotated around shaft 48 so that the upward tension of links 52 and the downward pressure created by spring 146 urge lever 44 in a counterclockwise direction. Lever 44 is prevented from moving in this direction by stop 51 which rests against framework 10. As a result of this construction, lever 44 will remain in its extreme downward position by itself without having to be held in that position by the operator. This assures a positive latching wherein tubes 82, 130, remain tightly sealed within the ends of canister 22 without need for the operator to maintain pressure on handle 46.

Either before or after piercing tubes 82', 130, have been punched through canister 22 so that spring 146 maintains them tightly against the walls of canister 22 to provide an airtight seal, inlet fitting 102 is connected to a source of air or other fluid pressure. Similarly, outlet fitting is connected to an outlet conduit. As air pressure is introduced through the top of canister 22 through upper tube 130, it forces the fluid contents of canister 22 out through lower tube 82, thereby increasing the velocity at which the contents are removed. There is no need to invert the canister after it has been tapped to remove the contents. Further, because upper tube introduces the air pressure into the top of canister- 22, the air does not bubble through the fluid contents therein as is likely with previous devices in which the air is introduced at the bottom.

ln canister tapping devices where both holes are made in the bottom of canister, once the canister is pressurized the pressure cannot be relieved without inverting the canister because liquid, not air, would be withdrawn. The canister tapping device of this invention however permits the relieving of air pressure without inverting the canister.

A plurality of canister tapping devices may be connected in series by connecting outlet fitting 100 of the first canister tapping device to inlet fitting 102 of the second and by repeating this type of connection for each additional tapping device in the series. A canister is used with each tapping device, and the contents of the canisters are ultimately withdrawn from outlet fitting 100 of the last canister tapping device in the serres.

Top 40 provides an overhang which embraces and provides support for the top end of canister 22 so that leakage is prevented in the event that the top of canister 22 bulges upwardly. If this happens the top of canister 22 will engage the lower portion of top 40 and top 40 will prevent any additional distortion. v

' A superior method of scaling is provided by the canister tapping device of this inventio'nb'ecause piercing tubes 82, 130, engage the can perpendicularly so that O-rings 84, 132, are pressed evenly around the apertures formed in the ends of canister 22. Also, previous canister opening devices utilized piercing tubes which engaged the can obliquely, causing a lateral force upon the piercing tip and maximizing dulling of the piercing tip. Dulling of the piercing tip in the present device is minimized by the fact that it meets the canister perpendicularly.

Spring 146 accelerates the piercing action, thereby preventing any substantial leakage during the piercing operation. In addition spring 146 maintains force upon both piercing tubes to keep elastomeric Q-rings 84, 132, compressed against canister 22 to prevent leakage.

Because air pressure is introduced into the top of canister 22 instead of at the bottom, there is no bubbling of air through the liquid in the container. When some liquids have a gas propelled through them they dissolve the gas. This problem is avoided by the canister tapping device of this invention.

When the canister tapping device is not in use, handle 46 may be placed in its extreme upward position so that piercing and second piercing tubes respectively; said first and second piercing tubes being movable toward each other to a closed position and being movable away from each other to a spread position; a movable mechanism interconnecting said punch levers; and moving means connected to said mechanism for moving it to cause said piercing tubes to move from the their spread position to their closed position; said frame being adapted to support said canister between said piercing tubes;

' said piercing tubes being spaced from said canister when in tubes 82, 130, are withdrawn into base 28 and top 40, respectively, thereby protecting them from being dulled or damaged.

The only portions of the canister tapping device which apply pressure to canister 22 are the two piercing tubes 82, 130. Since no other portion of the canister tapping device applies pressure to canister'22, there is no distortion or bending of the canister except at the point where it is penetrated by the tubes. Piercing tubes 82, 130, slant inwardly toward framework 10 and "thereby retain canister 22 between flanges l6, 18, of framework 10 in a firm manner.

When other canister taps are utilized, removal of the piercing tubes from the canister while the canister is still pressurized makes it likely that the left over contents in the bottom of the canister will spray into the atmosphere when pressure within the canister rushes out through the puncture in the bottom. This presents a safety hazard when the contents of the canister are toxic or otherwise injurious to people. Because the canister tapping device of this invention forms a tap at the top of the canister, it is possible to vent the pressure from the top before removing the piercing tubes, thereby eliminating the danger of spraying contents left in the bottom.

in view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

What we claim is:

1. A canister tapping device comprising a support frame adapted to support a canister having opposite walls and containing a fluid; first and second punch levers pivotally mounted in spaced relation on said frame and carrying first their spread position, being sufficiently close together to embrace and pierce said opposite walls of said container when in their closed position and said piercing tubes being mounted on said punch levers in predetermined positions so that their longitudinal axes point towards said frame when in their closed position.

2. The canister tapping device of claim 1 wherein elastomeric means are provided on each of said piercing tubes for engaging said canister when said tubes puncture its walls, thereby creating airtight seals around the margins of the punctures made by said piercing tubes.

3. The canister tapping device of claim I wherein said mechanism includes a rocker arm pivotally connected to said frame, a tension member pivotally connecting said first tube mounting means to one end of said rocker arm, another tension member pivotally connecting said second tube mounting means to the other end of said rocker arm.

4. The canister tapping device of claim 3 wherein said moving means is a lever pivotally connected to said frame and at least one link is pivotally connected at its opposite ends to said lever and said rocker arm respectively.

5. The canister tapping device of claim 1 wherein said moving means is a lever having a shaft at one of its ends pivotally mounted to said frame, said shaft being embraced by a springbiased block movably mounted on said frame, said shaft being movable against the bias of said spring in a direction perpendicular to the rotational axis of said shaft.

6. A canister tapping device comprising a support frame adapted to support a canister containing a fluid, said frame including a portion which embraces one end of said canister and including another portion positioned adjacent the opposite end of said canister; a piercing tube movably mounted on said other portion of said frame by tube mounting means, said piercing tube being movable from a first position wherein it is spaced from said canister to a second position wherein it punctures the canister wall in said opposite end of said canister; mechanism connected to said tube mounting means for moving said piercing tube between its first and second positions; and a lever pivotally connected to said frame, said mechanism being pivotally connected to said lever at a point spaced from the pivotal axis of said lever, said pivotal connection of said lever to said frame being provided by a shaft at one end of said lever which is rotatably mounted to said frame, said shaft being embraced by a spring-biased block movably mounted on said frame, said shaft being movable against the bias of said spring-baised block in a direction perpendicular to the rotational axis of said shaft. 

1. A canister tapping device comprising a support frame adapted to support a canister having opposite walls and containing a fluid; first and second punch levers pivotally mounted in spaced relation on said frame and carrying first and second piercing tubes respectively; said first and second piercing tubes being movable toward each other to a closed position and being movable away from each other to a spread position; a movable mechanism interconnecting said punch levers; and moving means connected to said mechanism for moving it to cause said piercing tubes to move from the their spread position to their closed position; said frame being adapted to support said canister between said piercing tubes; said piercing tubes being spaced from said canister when in their spread position, being sufficiently close together to embrace and pierce said opposite walls of said container when in their closed position and said piercing tubes being mounted on said punch levers in predetermined positions so that their longitudinal axes point towards said frame when in their closed position.
 2. The canister tapping device of claim 1 wherein elastomeric means are provided on each of said piercing tubes for engaging said canister when said tubes puncture its walls, thereby creating airtight seals around the margins of the punctures made by said piercing tubes.
 3. The canister tapping device of claim 1 wherein said mechanism includes a rocker arm pivotally connected to said frame, a tension member pivotally connecting said first tube mounting means to one end of said rocker arm, another tension member pivotally connecting said second tube mounting means to the other end of said rocker arm.
 4. The canister tapping device of claim 3 wherein said moving means is a lever pivotally connected to said frame and at least one link is pivotally connected at its opposite ends to said lever and said rocker arm respectively.
 5. The canister tapping device of claim 1 wherein said moving means is a lever having a shaft at one of its ends pivotally mounted to said frame, said shaft being embraced by a spring-biased block movably mounted on said frame, said shaft being movable against the bias of said spring in a direction perpendicular to the rotational axis of said shaft.
 6. A canister tapping device comprising a support frame adapted to support a canister containing a fluid, said frame including a portion which embraces one end of said canister and including another portion positioned adjacent the opposite end of said canister; a piercing tube movably mounted on said other portion of said frame by tube mounting means, said piercing tube being movable from a first position wherein it is spaced from said canister to a second position wherein it punctures the canister wall in said opposite end of said canister; mechanism connected to said tube mounting means for moving said piercing tube between its first and second positions; and a lever pivotally connected to said frame, said mechanism being pivotally connected to said Lever at a point spaced from the pivotal axis of said lever, said pivotal connection of said lever to said frame being provided by a shaft at one end of said lever which is rotatably mounted to said frame, said shaft being embraced by a spring-biased block movably mounted on said frame, said shaft being movable against the bias of said spring-baised block in a direction perpendicular to the rotational axis of said shaft. 